Electromagnetic device.



" My. invention is largely applicable for use -ji'nconnection withrelays in telephone work A .,Bnoros`,z forCHICAGQ ILLINOIS, iis-SIGNORrro THE AMERICAN ELECTRIC i *A TELEPHONE'CO., OF CHICAGO, ILLINOIS.

yer.ncriaoiviiianuario DEVICE.

all 'itmay concern:

" 'Be it known that'l', EINAR A. Biioros, a citizen ofthe United States,residing in'Chicago, in the, countyof Cook and State of lllivnois, haveinvented a certain new and usevices, of which the following is a full,clear, concise, and lenact description, reference be- -iiig had to theaccompanying drawing, forni- 1 in ga'. part'of this specification.

y invent-'ion relates to electro-magnetic devices and has foritsvparticular object the 'provision of such a. device which will Vbesubstantially uniformly responsive to non con- :tinuous currents.

` 'whereit is necessary to have suchrelays'uni- -forlly-responsive toalternating currents for instance; .In'aspecial application of theinventioii this is particularly true where such ire-lays are .usedas-pilot'relays in .an alter- ;natingcurrent ringing circuit.

VYI'wciuld describe my invention more in detail'by reference totheaccompanying drawing` illustrating. my embodiment thereof, in

Figure 1 shows aside view. of a relay constructed in: accordance withmy`\invention. Fig.,2 represents the same relay iin-its connection withapilot circuit, and Fig. 3"shows mere diagrammatically the windingarrangements.

Like'charac'ters of reference indicate like parts throughout th'edifferent figures. '"Referring more particularly to Fig. 1 I

have shown the relay as consisting of acore 1 provided with end piecesQ-TQ, upon which *is wound la suitable coil ofwire 3, the wire .beinghere shown in cross. section. An iniclosing ,shell 'A4, secured to thecore 1, by`

means of a nut 5, passes around the electro- `magnet consisting of thecore 1 and the winding 3, andv isili electro-magnetic relation to anarmature 6, pivoted before the bearing 7 ,I by means of the knife bladelever 8. The armature 6, is attracted toward the shell 4, landthe Ycore1, wh'encurrent isv present in the winding 3, asis well understood. Theattraction of the armature 6, raises' the lever 8, and4 allows springs 9and 10 to come into 'contact-,thus forming a relay. The winding.-'consists of two coils,'coil 11 and coil 12, which are 'insulated fromeach other, but

which are preferablyl wound in parallel ,to

Specification of Letters Patent.

Application led May 23, 1908. Serial No. 434,476.

get the maX'irniiii'i` inductive effects between them. The coil 12,thusbeing on the saine vcore with the coil 11.

It islthe object of my improved invention to make thisl electro magneticdevice responsive substantially uniformly to an alter-` nating current.

. It has been found in practice impracticable to take an ordinary relayfor instance.

'impress alternating eurent upon` it and have it draw up its armatureand then keep it in Patent-ea Nov. 2, 1909. i

its attracted position while the alternate cui'- y rent is flowing. -ltis usual under suc i conditions that the armature shatters.

To prevent this shattering,'in other' words to obtain a uniform'niagiietic effect is the object of my invention. l accomplished thisinthe specific case' shown in the illustrations by connecting a winding13, in series with the coll 12. This winding 13. 'is n'iounted upon asuitable core, 14, which is also inen A ductively related lo thearmature The core 14, is also magnetically assi'iciated` with the shelli, so that a goed magnetic path is provided when current is present inthe winding 13 to attract the armature 6. The advantage of this4arrangement willv now be apparent. When an alternating current isimpressed upon the coil 11, for instance, of the generator 15, throughthe interposition of the switch 16, an induced current will be generatedin the coil 12, which induced current liows serially through thewinding'13. lt will also be seen that the current in the winding 13,will not be in. phase with the current inthe coil 11. Thus due to thea1ternating current as given by the generator 15, a certain alternatingcurrentv will iiow through the coil 11, and at the Sametime a currentwill flow through the winding 13, which is not in phase with the currentin the coil 11. Thus niagneticattractions duetto the coil 11 and thewinding 13 are superposed upon thearniature '6, and it can be soarranged, if desired, that the attraction due to the winding13 whennearing ainaxiniuin in the magnetic attraction due to the coil 11, f ischanging its sign.

From the -illustration'in lFig-2` it will be 4 seen therefore that thearmature 6,'inay be uniformly attracted without shattering, thus 18. Amodification shown in Fig. A3,

where the coil 11, andthe windin 13, arel onthe same core the winding13,y yowever 'receiving its current from the second 19, oi

l armature under the combined magnetic influeiice of both cores, saidtwo cores forming portions ot' independent magnetic circuits and meanslwhereby the `second coil receives its energizing current iin'luctivelyfrom the i;

first aforesaid coil.` I

2. A tiuctuating current electro-magnetic device having twoelectro-magnets havingseparate cores forming portions of two distinctmagnetic circuits, and one-adapted to receive its` current i'roin aiiuctuating current source', andthe other adapted to receive its currentinductively from the former.

3. 'A fiuctuating current electro-nn-ignetic f device having twoelectro-magnets having .separate cores foi-innig portions of twodistinct. magnetic circuits, one `adapted to receive its current tronia` fluctuating'current source, and the other Iadapted to receive itscurrent.inductively troni the fornicr, and an armature coninioirto bothelectro-'magnets'.

4. A fluctuating current electro-magnetic device 'having twovelectro-niagnets having separate cores forming `portions of twodistiiictinagiietic circuits,- oiie adapted to re-.

ceive its current l'roin a fluctuating current source,pa secondary fcoil in inductive lrelation to said first electro-magnet and the 4otherrey ceivin its current from said secondary coil` in in uctive -relationto the iirstl aforesaid-i.' -f

electro-magnet. i

5. A uctuating current electro-magnetic device lhaving tivoelectro-magnets having separate cores forming portions of two distinctmagneticfcircuits, one adapted to' lljeceive its current from ,afluctuating current` source a secondary coil in inductivev relation tosaid first electro-magnet and the otherre-v ceiving its currentfrom-said secondary coil in inductive relation to therirst aforesaidIelectro-magnet, and an armature common to l. fif'f ..60 C. jAiluctuatiiig current" electro-magnetic both electioqnagnets.'4

device consisting oi'ntwo electro-magnets each having an operatingcoil,one of .said coils receiving its current from a fluctuatingcurrentsour'cma secondary windin Ain in ductive relation to said firstcoil an `superl imposed. thereon, and included. in circuit with saidsecond coil, said two electrofinag-4v g nets haviiigcores included indiierent mag netic circuits, andan armature' under-thecoinliineflinfluence of both electro'-magnets.y T. A' uctuating currentelectro-magnetic device having two electro-magnets,l oneada pted. toreceive its current from a uctuating current. source, and the otheradapted" fornicrg. and an' armature underithe com-f` biiied influence ofsaid electro-magnets and Y, adapted to be held in itsfully attractedcon-. dition 'when said first electro-magnet. is enery gixed byuctnatiiig currents. i

Iii witness whereof, I hereunto subscribe my name this 16th day of May1908.`

EINAR A. BROFOS 'Witnesses Il. I. CLAUsizx, R. F. Roose.

75 to receive its current inductively from the"

